1. Technical Field
The present invention relates to a light control apparatus and a projector.
2. Related Art
There is a known projector including a light source apparatus, a light modulation apparatus that modulates a light flux emitted from the light source apparatus, a light control apparatus that controls the amount of light flux to be incident on the light modulation apparatus, and a projection optical apparatus that enlarges and projects the light flux modulated by the light modulation apparatus. Since a projector is required to be portable because it is carried to and used in a variety of places in many cases, a light control apparatus that allows the size of the projector to be reduced has been proposed (see JP-A-2009-216906, for example).
The light control apparatus described in JP-A-2009-216906 is disposed between a pair of lens arrays for uniformly illuminating an image formation area of the light modulation apparatus with a light flux, that is, between a first lens array disposed on the upstream side of the optical path and a second lens array disposed on the downstream side of the optical path. A pair of light blocking members are so disposed that they do not overlap with pivotal axes of a pair of gears (pivotal members), and the pivotal axes are so disposed that they overlap with the second lens array. The configuration described above allows the distance between the first lens array and the light blocking members to be reduced and hence the size of the light control apparatus to be reduced as compared with a case where the light blocking members overlap with the pivotal axes or a case where the pivotal axes are located outside the second lens array in the width direction thereof.
In the light control apparatus described in JP-A-2009-216906, however, in which the gears are separated far away from the first lens array toward the downstream side of the optical path so that the distance between the first lens array and the light blocking members is reduced, the radii of the gears are not reduced in some cases. The distance between the pair of lens arrays can be reduced but the width of the light control apparatus in the direction perpendicular to the optical axis of the light flux may not be reduced, disadvantageously resulting in insufficient reduction of the size of the projector. Further, in a maximum light blocking state (see FIG. 9 in JP-A-2009-216906), in which the pair of light blocking members are so positioned that the tips thereof are separated from each other by a certain amount, the amount of light passing through the light control apparatus may not be sufficiently reduced in the maximum light blocking state or the light control may not be smoothly performed from a minimum light blocking state to the maximum light blocking state.